Does anyone know of a good fix or replacement for the Kazuma 150 chain tensioner? The tensioner does not seem to have enough spring force to keep from jumping the chain. My son and I have played with it a number of times in the last 6 months and finally thought we would ask if someone has a good solution.

Thanks...

 

I had a problem with the chain tensioner on my 150. I solved it by getting a 250.